Pileus Git - ~andy/gtk/blob - gtk/gtkadjustment.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GTK+ Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #include "config.h"
  28 #include "gtkadjustment.h"
  29 #include "gtkmarshalers.h"
  30 #include "gtkprivate.h"
  31 #include "gtkintl.h"
  32 #include "gtkalias.h"
  33
  34 enum
  35 {
  36   PROP_0,
  37   PROP_VALUE,
  38   PROP_LOWER,
  39   PROP_UPPER,
  40   PROP_STEP_INCREMENT,
  41   PROP_PAGE_INCREMENT,
  42   PROP_PAGE_SIZE
  43 };
  44
  45 enum
  46 {
  47   CHANGED,
  48   VALUE_CHANGED,
  49   LAST_SIGNAL
  50 };
  51
  52
  53 static void gtk_adjustment_get_property                (GObject      *object,
  54                                                         guint         prop_id,
  55                                                         GValue       *value,
  56                                                         GParamSpec   *pspec);
  57 static void gtk_adjustment_set_property                (GObject      *object,
  58                                                         guint         prop_id,
  59                                                         const GValue *value,
  60                                                         GParamSpec   *pspec);
  61 static void gtk_adjustment_dispatch_properties_changed (GObject      *object,
  62                                                         guint         n_pspecs,
  63                                                         GParamSpec  **pspecs);
  64
  65 static guint adjustment_signals[LAST_SIGNAL] = { 0 };
  66
  67 G_DEFINE_TYPE (GtkAdjustment, gtk_adjustment, GTK_TYPE_OBJECT)
  68
  69 static void
  70 gtk_adjustment_class_init (GtkAdjustmentClass *class)
  71 {
  72   GObjectClass *gobject_class = G_OBJECT_CLASS (class);
  73
  74   gobject_class->set_property                = gtk_adjustment_set_property;
  75   gobject_class->get_property                = gtk_adjustment_get_property;
  76   gobject_class->dispatch_properties_changed = gtk_adjustment_dispatch_properties_changed;
  77
  78   class->changed = NULL;
  79   class->value_changed = NULL;
  80
  81   /**
  82    * GtkAdjustment:value:
  83    *
  84    * The value of the adjustment.
  85    *
  86    * Since: 2.4
  87    */
  88   g_object_class_install_property (gobject_class,
  89                                    PROP_VALUE,
  90                                    g_param_spec_double ("value",
  91                                                         P_("Value"),
  92                                                         P_("The value of the adjustment"),
  93                                                         -G_MAXDOUBLE,
  94                                                         G_MAXDOUBLE,
  95                                                         0.0,
  96                                                         GTK_PARAM_READWRITE));
  97
  98   /**
  99    * GtkAdjustment:lower:
 100    *
 101    * The minimum value of the adjustment.
 102    *
 103    * Since: 2.4
 104    */
 105   g_object_class_install_property (gobject_class,
 106                                    PROP_LOWER,
 107                                    g_param_spec_double ("lower",
 108                                                         P_("Minimum Value"),
 109                                                         P_("The minimum value of the adjustment"),
 110                                                         -G_MAXDOUBLE,
 111                                                         G_MAXDOUBLE,
 112                                                         0.0,
 113                                                         GTK_PARAM_READWRITE));
 114
 115   /**
 116    * GtkAdjustment:upper:
 117    *
 118    * The maximum value of the adjustment.
 119    * Note that values will be restricted by
 120    * <literal>upper - page-size</literal> if the page-size
 121    * property is nonzero.
 122    *
 123    * Since: 2.4
 124    */
 125   g_object_class_install_property (gobject_class,
 126                                    PROP_UPPER,
 127                                    g_param_spec_double ("upper",
 128                                                         P_("Maximum Value"),
 129                                                         P_("The maximum value of the adjustment"),
 130                                                         -G_MAXDOUBLE,
 131                                                         G_MAXDOUBLE,
 132                                                         0.0,
 133                                                         GTK_PARAM_READWRITE));
 134
 135   /**
 136    * GtkAdjustment:step-increment:
 137    *
 138    * The step increment of the adjustment.
 139    *
 140    * Since: 2.4
 141    */
 142   g_object_class_install_property (gobject_class,
 143                                    PROP_STEP_INCREMENT,
 144                                    g_param_spec_double ("step-increment",
 145                                                         P_("Step Increment"),
 146                                                         P_("The step increment of the adjustment"),
 147                                                         -G_MAXDOUBLE,
 148                                                         G_MAXDOUBLE,
 149                                                         0.0,
 150                                                         GTK_PARAM_READWRITE));
 151
 152   /**
 153    * GtkAdjustment:page-increment:
 154    *
 155    * The page increment of the adjustment.
 156    *
 157    * Since: 2.4
 158    */
 159   g_object_class_install_property (gobject_class,
 160                                    PROP_PAGE_INCREMENT,
 161                                    g_param_spec_double ("page-increment",
 162                                                         P_("Page Increment"),
 163                                                         P_("The page increment of the adjustment"),
 164                                                         -G_MAXDOUBLE,
 165                                                         G_MAXDOUBLE,
 166                                                         0.0,
 167                                                         GTK_PARAM_READWRITE));
 168
 169   /**
 170    * GtkAdjustment:page-size:
 171    *
 172    * The page size of the adjustment.
 173    * Note that the page-size is irrelevant and should be set to zero
 174    * if the adjustment is used for a simple scalar value, e.g. in a
 175    * #GtkSpinButton.
 176    *
 177    * Since: 2.4
 178    */
 179   g_object_class_install_property (gobject_class,
 180                                    PROP_PAGE_SIZE,
 181                                    g_param_spec_double ("page-size",
 182                                                         P_("Page Size"),
 183                                                         P_("The page size of the adjustment"),
 184                                                         -G_MAXDOUBLE,
 185                                                         G_MAXDOUBLE,
 186                                                         0.0,
 187                                                         GTK_PARAM_READWRITE));
 188
 189   adjustment_signals[CHANGED] =
 190     g_signal_new (I_("changed"),
 191                   G_OBJECT_CLASS_TYPE (class),
 192                   G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
 193                   G_STRUCT_OFFSET (GtkAdjustmentClass, changed),
 194                   NULL, NULL,
 195                   _gtk_marshal_VOID__VOID,
 196                   G_TYPE_NONE, 0);
 197
 198   adjustment_signals[VALUE_CHANGED] =
 199     g_signal_new (I_("value_changed"),
 200                   G_OBJECT_CLASS_TYPE (class),
 201                   G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
 202                   G_STRUCT_OFFSET (GtkAdjustmentClass, value_changed),
 203                   NULL, NULL,
 204                   _gtk_marshal_VOID__VOID,
 205                   G_TYPE_NONE, 0);
 206 }
 207
 208 static void
 209 gtk_adjustment_init (GtkAdjustment *adjustment)
 210 {
 211   adjustment->value = 0.0;
 212   adjustment->lower = 0.0;
 213   adjustment->upper = 0.0;
 214   adjustment->step_increment = 0.0;
 215   adjustment->page_increment = 0.0;
 216   adjustment->page_size = 0.0;
 217 }
 218
 219 static void
 220 gtk_adjustment_get_property (GObject    *object,
 221                              guint       prop_id,
 222                              GValue     *value,
 223                              GParamSpec *pspec)
 224 {
 225   GtkAdjustment *adjustment = GTK_ADJUSTMENT (object);
 226
 227   switch (prop_id)
 228     {
 229     case PROP_VALUE:
 230       g_value_set_double (value, adjustment->value);
 231       break;
 232     case PROP_LOWER:
 233       g_value_set_double (value, adjustment->lower);
 234       break;
 235     case PROP_UPPER:
 236       g_value_set_double (value, adjustment->upper);
 237       break;
 238     case PROP_STEP_INCREMENT:
 239       g_value_set_double (value, adjustment->step_increment);
 240       break;
 241     case PROP_PAGE_INCREMENT:
 242       g_value_set_double (value, adjustment->page_increment);
 243       break;
 244     case PROP_PAGE_SIZE:
 245       g_value_set_double (value, adjustment->page_size);
 246       break;
 247     default:
 248       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 249       break;
 250     }
 251 }
 252
 253 static void
 254 gtk_adjustment_set_property (GObject      *object,
 255                              guint         prop_id,
 256                              const GValue *value,
 257                              GParamSpec   *pspec)
 258 {
 259   GtkAdjustment *adjustment = GTK_ADJUSTMENT (object);
 260   gdouble double_value = g_value_get_double (value);
 261
 262   switch (prop_id)
 263     {
 264     case PROP_VALUE:
 265       gtk_adjustment_set_value (adjustment, double_value);
 266       break;
 267     case PROP_LOWER:
 268       adjustment->lower = double_value;
 269       break;
 270     case PROP_UPPER:
 271       adjustment->upper = double_value;
 272       break;
 273     case PROP_STEP_INCREMENT:
 274       adjustment->step_increment = double_value;
 275       break;
 276     case PROP_PAGE_INCREMENT:
 277       adjustment->page_increment = double_value;
 278       break;
 279     case PROP_PAGE_SIZE:
 280       adjustment->page_size = double_value;
 281       break;
 282     default:
 283       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 284       break;
 285     }
 286 }
 287
 288 static void
 289 gtk_adjustment_dispatch_properties_changed (GObject     *object,
 290                                             guint        n_pspecs,
 291                                             GParamSpec **pspecs)
 292 {
 293   gboolean changed = FALSE;
 294   gint i;
 295
 296   G_OBJECT_CLASS (gtk_adjustment_parent_class)->dispatch_properties_changed (object, n_pspecs, pspecs);
 297
 298   for (i = 0; i < n_pspecs; i++)
 299     switch (pspecs[i]->param_id)
 300       {
 301       case PROP_LOWER:
 302       case PROP_UPPER:
 303       case PROP_STEP_INCREMENT:
 304       case PROP_PAGE_INCREMENT:
 305       case PROP_PAGE_SIZE:
 306         changed = TRUE;
 307         break;
 308       default:
 309         break;
 310       }
 311
 312   if (changed)
 313     gtk_adjustment_changed (GTK_ADJUSTMENT (object));
 314 }
 315
 316 GtkObject *
 317 gtk_adjustment_new (gdouble value,
 318                     gdouble lower,
 319                     gdouble upper,
 320                     gdouble step_increment,
 321                     gdouble page_increment,
 322                     gdouble page_size)
 323 {
 324   return g_object_new (GTK_TYPE_ADJUSTMENT,
 325                        "lower", lower,
 326                        "upper", upper,
 327                        "step-increment", step_increment,
 328                        "page-increment", page_increment,
 329                        "page-size", page_size,
 330                        "value", value,
 331                        NULL);
 332 }
 333
 334 /**
 335  * gtk_adjustment_get_value:
 336  * @adjustment: a #GtkAdjustment
 337  *
 338  * Gets the current value of the adjustment. See
 339  * gtk_adjustment_set_value ().
 340  *
 341  * Return value: The current value of the adjustment.
 342  **/
 343 gdouble
 344 gtk_adjustment_get_value (GtkAdjustment *adjustment)
 345 {
 346   g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
 347
 348   return adjustment->value;
 349 }
 350
 351 void
 352 gtk_adjustment_set_value (GtkAdjustment *adjustment,
 353                           gdouble        value)
 354 {
 355   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 356
 357   value = CLAMP (value, adjustment->lower, adjustment->upper);
 358
 359   if (value != adjustment->value)
 360     {
 361       adjustment->value = value;
 362
 363       gtk_adjustment_value_changed (adjustment);
 364     }
 365 }
 366
 367 void
 368 gtk_adjustment_changed (GtkAdjustment *adjustment)
 369 {
 370   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 371
 372   g_signal_emit (adjustment, adjustment_signals[CHANGED], 0);
 373 }
 374
 375 void
 376 gtk_adjustment_value_changed (GtkAdjustment *adjustment)
 377 {
 378   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 379
 380   g_signal_emit (adjustment, adjustment_signals[VALUE_CHANGED], 0);
 381   g_object_notify (G_OBJECT (adjustment), "value");
 382 }
 383
 384 void
 385 gtk_adjustment_clamp_page (GtkAdjustment *adjustment,
 386                            gdouble        lower,
 387                            gdouble        upper)
 388 {
 389   gboolean need_emission;
 390
 391   g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 392
 393   lower = CLAMP (lower, adjustment->lower, adjustment->upper);
 394   upper = CLAMP (upper, adjustment->lower, adjustment->upper);
 395
 396   need_emission = FALSE;
 397
 398   if (adjustment->value + adjustment->page_size < upper)
 399     {
 400       adjustment->value = upper - adjustment->page_size;
 401       need_emission = TRUE;
 402     }
 403   if (adjustment->value > lower)
 404     {
 405       adjustment->value = lower;
 406       need_emission = TRUE;
 407     }
 408
 409   if (need_emission)
 410     gtk_adjustment_value_changed (adjustment);
 411 }
 412
 413 #define __GTK_ADJUSTMENT_C__
 414 #include "gtkaliasdef.c"